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By NASA
Illustration of the main asteroid belt, orbiting the Sun between Mars and JupiterNASA NASA’s powerful James Webb Space Telescope includes asteroids on its list of objects studied and secrets revealed.
A team led by researchers at the Massachusetts Institute of Technology (MIT) in Cambridge repurposed Webb’s observations of a distant star to reveal a population of small asteroids — smaller than astronomers had ever detected orbiting the Sun in the main asteroid belt between Mars and Jupiter.
The 138 new asteroids range from the size of a bus to the size of a stadium — a size range in the main belt that has not been observable with ground-based telescopes. Knowing how many main belt asteroids are in different size ranges can tell us something about how asteroids have been changed over time by collisions. That process is related to how some of them have escaped the main belt over the solar system’s history, and even how meteorites end up on Earth.
“We now understand more about how small objects in the asteroid belt are formed and how many there could be,” said Tom Greene, an astrophysicist at NASA’s Ames Research Center in California’s Silicon Valley and co-author on the paper presenting the results. “Asteroids this size likely formed from collisions between larger ones in the main belt and are likely to drift towards the vicinity of Earth and the Sun.”
Insights from this research could inform the work of the Asteroid Threat Assessment Project at Ames. ATAP works across disciplines to support NASA’s Planetary Defense Coordination Office by studying what would happen in the case of an Earth impact and modeling the associated risks.
“It’s exciting that Webb’s capabilities can be used to glean insights into asteroids,” said Jessie Dotson, an astrophysicist at Ames and member of ATAP. “Understanding the sizes, numbers, and evolutionary history of smaller main belt asteroids provides important background about the near-Earth asteroids we study for planetary defense.”
Illustration of the James Webb Space TelescopeNASA The team that made the asteroid detections, led by research scientist Artem Burdanov and professor of planetary science Julien de Wit, both of MIT, developed a method to analyze existing Webb images for the presence of asteroids that may have been inadvertently “caught on film” as they passed in front of the telescope. Using the new image processing technique, they studied more than 10,000 images of the star TRAPPIST-1, originally taken to search for atmospheres around planets orbiting the star, in the search for life beyond Earth.
Asteroids shine more brightly in infrared light, the wavelength Webb is tuned to detect, than in visible light, helping reveal the population of main belt asteroids that had gone unnoticed until now. NASA will also take advantage of that infrared glow with an upcoming mission, the Near-Earth Object (NEO) Surveyor. NEO Surveyor is the first space telescope specifically designed to hunt for near-Earth asteroids and comets that may be potential hazards to Earth.
The paper presenting this research, “Detections of decameter main-belt asteroids with JWST,” was published Dec. 9 in Nature.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
For news media:
Members of the news media interested in covering this topic should reach out to the NASA Ames newsroom.
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By NASA
NASA’s Dawn spacecraft captured this image of Vesta as it left the giant asteroid’s orbit in 2012. The framing camera was looking down at the north pole, which is in the middle of the image.NASA/JPL-Caltech/UCLA/MPS/DLR/IDA Known as flow formations, these channels could be etched on bodies that would seem inhospitable to liquid because they are exposed to the extreme vacuum conditions of space.
Pocked with craters, the surfaces of many celestial bodies in our solar system provide clear evidence of a 4.6-billion-year battering by meteoroids and other space debris. But on some worlds, including the giant asteroid Vesta that NASA’s Dawn mission explored, the surfaces also contain deep channels, or gullies, whose origins are not fully understood.
A prime hypothesis holds that they formed from dry debris flows driven by geophysical processes, such as meteoroid impacts, and changes in temperature due to Sun exposure. A recent NASA-funded study, however, provides some evidence that impacts on Vesta may have triggered a less-obvious geologic process: sudden and brief flows of water that carved gullies and deposited fans of sediment. By using lab equipment to mimic conditions on Vesta, the study, which appeared in Planetary Science Journal, detailed for the first time what the liquid could be made of and how long it would flow before freezing.
Although the existence of frozen brine deposits on Vesta is unconfirmed, scientists have previously hypothesized that meteoroid impacts could have exposed and melted ice that lay under the surface of worlds like Vesta. In that scenario, flows resulting from this process could have etched gullies and other surface features that resemble those on Earth.
To explore potential explanations for deep channels, or gullies, seen on Vesta, scientists used JPL’s Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE, to simulate conditions on the giant asteroid that would occur after meteoroids strike the surface.NASA/JPL-Caltech But how could airless worlds — celestial bodies without atmospheres and exposed to the intense vacuum of space — host liquids on the surface long enough for them to flow? Such a process would run contrary to the understanding that liquids quickly destabilize in a vacuum, changing to a gas when the pressure drops.
“Not only do impacts trigger a flow of liquid on the surface, the liquids are active long enough to create specific surface features,” said project leader and planetary scientist Jennifer Scully of NASA’s Jet Propulsion Laboratory in Southern California, where the experiments were conducted. “But for how long? Most liquids become unstable quickly on these airless bodies, where the vacuum of space is unyielding.”
The critical component turns out to be sodium chloride — table salt. The experiments found that in conditions like those on Vesta, pure water froze almost instantly, while briny liquids stayed fluid for at least an hour. “That’s long enough to form the flow-associated features identified on Vesta, which were estimated to require up to a half-hour,” said lead author Michael J. Poston of the Southwest Research Institute in San Antonio.
Launched in 2007, the Dawn spacecraft traveled to the main asteroid belt between Mars and Jupiter to orbit Vesta for 14 months and Ceres for almost four years. Before ending in 2018, the mission uncovered evidence that Ceres had been home to a subsurface reservoir of brine and may still be transferring brines from its interior to the surface. The recent research offers insights into processes on Ceres but focuses on Vesta, where ice and salts may produce briny liquid when heated by an impact, scientists said.
Re-creating Vesta
To re-create Vesta-like conditions that would occur after a meteoroid impact, the scientists relied on a test chamber at JPL called the Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE. By rapidly reducing the air pressure surrounding samples of liquid, they mimicked the environment around fluid that comes to the surface. Exposed to vacuum conditions, pure water froze instantly. But salty fluids hung around longer, continuing to flow before freezing.
The brines they experimented with were a little over an inch (a few centimeters) deep; scientists concluded the flows on Vesta that are yards to tens of yards deep would take even longer to refreeze.
The researchers were also able to re-create the “lids” of frozen material thought to form on brines. Essentially a frozen top layer, the lids stabilize the liquid beneath them, protecting it from being exposed to the vacuum of space — or, in this case the vacuum of the DUSTIE chamber — and helping the liquid flow longer before freezing again.
This phenomenon is similar to how on Earth lava flows farther in lava tubes than when exposed to cool surface temperatures. It also matches up with modeling research conducted around potential mud volcanoes on Mars and volcanoes that may have spewed icy material from volcanoes on Jupiter’s moon Europa.
“Our results contribute to a growing body of work that uses lab experiments to understand how long liquids last on a variety of worlds,” Scully said.
Find more information about NASA’s Dawn mission here:
https://science.nasa.gov/mission/dawn/
News Media Contacts
Gretchen McCartney
Jet Propulsion Laboratory, Pasadena, Calif.
818-287-4115
gretchen.p.mccartney@jpl.nasa.gov
Karen Fox / Molly Wasser
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov
2024-178
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Last Updated Dec 20, 2024 Related Terms
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By European Space Agency
Less than a week after its launch, the Copernicus Sentinel-1C satellite has delivered its first radar images of Earth – offering a glimpse into its capabilities for environmental monitoring. These initial images feature regions of interest, including Svalbard in Norway, the Netherlands, and Brussels, Belgium.
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By NASA
3 Min Read Matt Dominick’s X Account: A Visual Journey from Space
We are lucky to have had the opportunity to fly in space and feel a responsibility to share with humanity the incredible views of the Earth and the cosmos.
Matt dominick
NASA Astronaut
NASA astronaut and Expedition 72 Flight Engineer Matthew Dominick launched to the International Space Station on March 3, 2024 as the commander of NASA’s SpaceX Crew-8 mission. As a flight engineer aboard the orbiting laboratory, Dominick conducted scientific research while capturing breathtaking views of Earth and beyond from the ultimate vantage point—250 miles above the planet.
Dominick’s X account (@dominickmatthew) has become a visual diary, showcasing the beauty of our planet captured from low Earth orbit during his 235 days in space. From the ethereal glow of auroras dancing across the atmosphere to comets rising up over the horizon during an orbital sunrise, each meticulously captured image reflects his dedication to sharing the wonders of space exploration through social media. He goes beyond simply posting pictures; he reveals the techniques behind his astrophotography, including camera settings and insights into his creative process, inviting followers to appreciate the artistry involved.
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Matt Dominick shared this timelapse video to his X account in August 2024, showing the Moon setting into streams of red and green aurora.Matt Dominick See the full X post here.
Amid his daily astronaut duties, Dominick dedicated personal time to this endeavor, amassing nearly 500,000 captivating photos of Earth and snapshots of life aboard the International Space Station, while having traveled 99,708,603 total statue miles around our home planet. Through his lens(es), he invited us to experience the awe of space while highlighting the realities of life in orbit, fostering an authentic connection with those who engage with his work.
Building on this commitment to connect, Dominick participated in the first-ever live X Spaces event from space, marking a new way for NASA astronauts to connect personally with followers. He shared insider tips on astrophotography from orbit and discussed the challenges and joys of capturing stunning images in microgravity. Concluding the event, he vividly narrated his live experience floating into the Cupola at sunset while orbiting over Paris just days before the 2024 Summer Olympic Games.
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A screen recording of the first X Spaces event from space featuring NASA astronaut Matt Dominick.NASA Dominick’s journey as an astronaut unfolds in real-time on his X account. He has captured the arrivals and departures of various spacecraft, documented dynamic weather events, and even participated in Olympic festivities. His stunning timelapses and behind-the-scenes videos offer an intimate look at life aboard the space station, beautifully illustrating the intricate interplay between science and wonder.
What sets Dominick’s account apart is his playful perspective. He invites his audience into lighthearted moments—whether he’s cleaning his retainer in microgravity, relishing the arrival of fresh fruit, or sharing insights from the ISS toolbox. By documenting and sharing these experiences, he demystifies the complexities of space travel, making it an accessible and relatable journey for all. Through his engaging posts, Dominick cultivates a deeper connection with his followers, encouraging them to share in the beauty and reality of life beyond our planet.
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Matt Dominick shared this video video to his X account in August 2024 after receiving fresh fruit aboard the International Space Station.Matt Dominick See the full X post here.
Visit Dominick’s X account (@dominickmatthew) to experience the wonders of space through his eyes, enriched by his remarkable journey of orbiting the Earth 3,760 times.
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Last Updated Dec 05, 2024 Related Terms
International Space Station (ISS) Astronauts Expedition 72 Humans in Space View the full article
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